Fixed sheduling bug where not enough retrieve mounts got triggered.

The queue size division by the number of existing mount is only valid for archive mounts
where the queue is shared by each mount. In the case of retrieves, the criteria should be considered
vid by vid and the number of exiting mounts should not matter.

scheduler/Scheduler.cpp

@@ -473,10 +473,13 @@ std::unique_ptr<TapeMount> Scheduler::getNextMount(const std::string &logicalLib
     } catch (std::out_of_range &) {
       existingMounts = 0;
     } 
+    uint32_t effectiveExistingMounts = 0;
+    if (m->type == common::dataStructures::MountType::Archive) effectiveExistingMounts = existingMounts;
     bool mountPassesACriteria = false;
-    if (m->bytesQueued / (1 + existingMounts) >= m_minBytesToWarrantAMount)
+    
+    if (m->bytesQueued / (1 + effectiveExistingMounts) >= m_minBytesToWarrantAMount)
       mountPassesACriteria = true;
-    if (m->filesQueued / (1 + existingMounts) >= m_minFilesToWarrantAMount)
+    if (m->filesQueued / (1 + effectiveExistingMounts) >= m_minFilesToWarrantAMount)
       mountPassesACriteria = true;
     if (!existingMounts && ((time(NULL) - m->oldestJobStartTime) > m->minArchiveRequestAge))
       mountPassesACriteria = true;